import sys

def load_file(file):
     try:
         with open(file) as in_file:
            load_text = in_file.read().strip().split('\n')
            load_text = [x.lower() for x in load_text]
            return load_text
     except IOError as e:
        print('文件{}打开发生{}错误'.format(file, e))
        sys.exit(1)